Intermetallic compounds of polymeric transition metal oxide alkoxides and catalytic use thereof

ABSTRACT

An intermetallic compound comprising the reaction product of a transition metal and a reducing metal of a higher oxidation potential than the transition metal obtained by the reaction of a polymeric transition metal oxide alkoxide and the reducing metal in the presence of a mono- or dialkyl phosphate or mixtures thereof in which each alkyl contains up to 10 carbon atoms; and catalyst components and systems for the polymerization of alpha olefins.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation in-part of copending commonlyassigned applications of the same inventive entity as follows: Ser. No.209,223; 209,224; 209,225; 209,226; 209,227; 209,228; 209,229, all filedNov. 24, 1980 and all now abandoned, Ser. No. 228,831, filed Jan. 27,1981 and now abondoned; and Ser. No. 483,054, filed Apr. 7, 1983 and nowPat. No. 4,513,095.

BACKGROUND OF THE INVENTION

This invention relates to intermetallic compounds of transition metaloxide alkoxides and processes for their production. More particularly,the invention affords catalyst precursors for interreaction with halideactivators to provide a catalyst component adapted for thepolymerization of alpha olefins.

Polyethylene, produced by solution or slurry processes at lowerpressures providing a linear high density resin, or in autoclave ortubular reactors at higher pressures, providing a long chain branchedlow density resin, has been an object of commercial production for manyyears.

It has been recognized that certain characteristics of the linear highdensity resins such as stiffness and abrasion resistance would usefullybe combined with valuable properties of the branched low density resinsuch as high impact toughness and stress crack resistance, and it hasbeen discovered that the interrelationship of these properties may beattributed in part to the nature and amount of side chain development.

Accordingly, linear low density polyethylene resins have now beenproduced in low pressure processes employing specialized catalystsystems, the resins being characterized by linearity and short chainbranching afforded by alkene comonomers (without significant long chainbranching), and offering narrow molecular weight distribution, improvedstrength properties, higher melt viscosity, high softening point,improved ESCR (Environmental Stress Crack Resistance) and improved lowtemperature brittleness. These and related properties provide advantagesto the user in such applications as blown film, wire and cable coating,cast film, co-extrusion, and injection and rotational molding.

It is an objective to manufacture such linear low density resins in aneconomic and efficient manner under the conditions existing in slurryreactors, and to accomplish such manufacture with the provision of resinof competitive product characteristics, employing catalyst systemshaving user acceptable residues.

The linear olefin polymers have typically been produced usingcoordination catalysts of the general type disclosed by Ziegler, thuscomprising a transition metal compound, usually a titanium halideadmixed with an organometallic compound such as alkyl aluminum. Thetransition metal component may be activated by reaction with a halidepromoter such as an alkyl aluminum halide. Among the improved catalystsof this type are those incorporating a magnesium component, usually byinteraction of magnesium or a compound thereof with the transition metalcomponent or the organometallic compounds, as by milling or chemicalreaction or association.

It is a further object to provide a catalyst for the polymerization ofalpha olefins affording a range of resin properties under varioussynthesis conditions.

A particular object is the preparation of linear low densitypolyethylene having a broadened molecular weight distribution.

BRIEF DESCRIPTION OF THE INVENTION

According to the present invention, transition metal-containingintermetallic compounds are prepared by the reaction of a transitionmetal alkoxide with at least one reducing metal, i.e., a metal having ahigher oxidation potential than the transition metal, in the presence ofcertain alkyl phosphates.

The alkyl phosphates used in the present invention are mono- anddialkylphosphates in which the alkyl groups contain up to about 10carbon atoms, and are preferably lower alkyl groups. These compounds arealso described as mono- and diprotic alkyl phosphates.

Transition metal alkoxides are well known particularly titaniumalkoxides, especially for their colligative properties in organicsolvents; see, for example, "The Polymeric Nature of TitaniumTetraethoxide in Solution", Bradley, et al., Inorg. Chem., Vol. 3, No.8, pp. 1163-65 (1969). In general, these alkoxides form oligomers andcondensation products, especially at elevated temperatures, which tendto form polymeric titanium oxide alkoxides, particularly in the courseof reaction with elecron-donor reactants, as exemplified by reactionwith water, i.e., hydrolysis. Apparently, similar results are obtainedwhen these alkoxides are reacted in the presence of alkyl phosphates asalready described herein. For ease of description, these materials willbe referred to as polymeric oxide alkoxides of the respective transitionmetals.

Regardless of the particular form which the alkoxide is visualized toadopt, in practice it is sufficient to recognize that the alkoxideoligomers apparently form a series of polymeric oxide alkoxides rangingfrom the dimer through cyclic forms to linear polymers of up toindefinite chain length during the course of the present processs. Ofcourse, it is expected that the polymeric oxide alkoxides can be formedseparately but the ease of formation of these alkoxides in situindicates the latter to be preferred.

The polymeric transition metal oxide alkoxides are reacted with areducing metal having an oxidation potential higher than the transitionmetal. Preferably a polymeric titanium oxide alkoxide is employedtogether with magnesium (or calcium, potassium, aluminum or zinc), asthe reducing metal.

The inventive process is accomplished by heating a mixture of theselected transition metal alkoxide, reducing metal, and alkyl phosphatesto a temperature at which color change occurs and gas evolution occurs.Heating is usually continued until gas evolution ceases.

In the preferred embodiment (to which illustrative reference is made inthe following text, as a matter of convenience), titaniumtetra-n-butoxide (TBT) is reacted with magnesium turnings and alkylphosphates, at a temperature of 50°-150° C., in a reaction vessel underautogeneous pressure. TBT may constitute the reaction medium, or ahydrocarbon solvent may be used. Ti/Mg molar ratios may vary from 1:0.1to 1:1 although for the most homogeneous reaction system astoichiometric relationship of Ti^(IV) to Mg° of 1:1 is preferred, withan amount of alkyl phosphate being about 1.5 mole per mole of Mg.

The hydrocarbon soluble catalyst precursor comprises predominently Tivalues in association with Mg values, in one or morestereoconfigurational complexes believed to constitute principallyoxygenated, at least partially reduced transition metal species. Someevidence of mixed oxidation states of the titanium values suggests aninterrelated system of integral species of Ti^(IV), Ti^(III), andTi^(II) values perhaps in a quasi-equilibrium relation at least underdynamic reaction conditions. The preferred precursor is believed,without limitation, to incorporate (Ti--O--Mg) bridging structures.

The intermetallic compounds have special interest as catalystprecursors, in supported or unsupported systems, for isomerization,dimerization, oligomerization or polymerization of alkenes, alkynes orsubstituted alkenes in the presence or absence of reducing agents oractivators, e.g., organometallic compounds of Group IA, IIA, IIIA or IIBmetals.

In the preferred utilization of such precursors, they are reacted with ahalide activator such as an alkyl aluminum halide, a silicon halide or aboron halide, and combined with an organometallic compound such as analuminum alkyl to form a catalyst system adapted particularly to thepolymerization of ethylene and comonomers, especially in slurrypolymerizations to provide a range of useful resins from LLDPE to HDPE.

DETAILED DESCRIPTION OF THE INVENTION

The transition metal component is an alkoxide, normally a titanium orzirconium alkoxide, comprising essentially -OR substitutuents where Rmay comprise up to 10 carbon atoms, preferably 2 to 5 carbon atoms, andmost preferably n-alkyl such as n-butyl. The selected component isnormally liquid under ambient conditions and the reaction temperaturesfor ease of handling, and to facilitate use of titanium component isalso hydrocarbon soluble.

It is generally preferred for facility in conducting the reaction toemploy transition metal compounds which comprise only alkoxidesubstituents, although other substituents may be contemplated where theydo not interfere with the reaction in the sense of detrimentallyaffecting performance in use. In general, the halide-free n-alkoxidesare employed although, for example, di-n-butoxy titanium dichloride andthe like may be suitably employed.

The transition metal component is provided in the highest oxidationstate for the transition metal, to provide the desiredstereoconfigurational structure, among other considerations. The termtransition metal is used in its customary broad sense to denote thetransition elements in which the penultimate electron shell is electrondeficient, but is illustrated principally by reference to the readilyavailable members of Group IVB. and VB of the Periodic Table. Othertransition metals forming stable alkoxides useable in olefinpolymerization or other catalytic processes may be employed as desired.Most suitably, especially for olefin polymerization, the alkoxide is atitanium or zirconium alkoxide. Suitable titanium compounds includetitanium tetraethoxide, as well as the related compounds incorporatingone or more alkoxy radicals including n-propoxy, iso-propoxy, n-butoxy,isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, tert-amyloxy, n-hexyloxy,n-heptyloxy, nonyloxy, and so forth. One or more transition metalalkoxides may be admixed for reaction, e.g., mixtures in all proportionsof titanium and zirconium alkoxides may be used.

Some evidence suggests that the rate of reaction of the normalderivatives decreases with increasing chain length and the ratedecreases with molecular complexity viz. tertiary, secondary, normal;hence these considerations may be taken into account in selecting apreferred derivative. In general, titanium tetrabutoxide has been foundeminently suitable for the practice of the present invention, andrelated tetraalkoxides are likewise preferred. It will be understoodthat mixed alkoxides are perfectly suitable, and may be employed whereconveniently available. Complex titanium alkoxides sometimes inclusiveof other metallic components may also be employed.

The reducing metal is supplied at least in part in the zero oxidationstate as a necessary element of the reaction system. A convenient sourceis the familiar turnings, or ribbon or powder. As supplied commercially,these materials may be in a passivated surface oxidized condition andmilling or grinding to provide at least some fresh surface may bedesirable, at least to control reaction rate. Such grinding or millingis not, however, a necessary step to the preparative process. Mixturesof reducing metals may also be conveniently employed particularly wherethe source of principal reducing metal is impure or is available as anamalgam with other metals, e.g., magnesium/aluminum. The reducing metalmay be supplied as convenient, in the form of a slurry in the titaniumcomponent and/or hydrocarbon diluent, or may be added directly to thereactor.

The interaction of these components is conveniently carried out in anenclosed reactor, preferably coupled with reflux capacity for volatilecomponents at the elevated temperatures produced in the reaction vessel.Autogenous pressure is employed, as the reaction proceeds smoothly underambient conditions, with heating to initiate and maintain the reaction.As in any such reaction stirring is preferred simply to avoid caking orcoating of vessel surfaces, to provide intimate admixture of components,and to ensure a homogeneous reaction system.

Usually, a hydrocarbon solvent such as hexane, heptane, octane, decalin,mineral spirits and the like is also used to facilitate intermixture ofcomponents, heat transfer and maintenance of a homogeneous reactionsystem. Saturated hydrocarbons are preferred, having a boiling point inthe range of 60° to 190° C. The liquid transition metal component alsomay serve at least in part as the reaction medium, especially where noadded solvent is employed. The reaction involves a stage whereadditional volatile components form azeotropes with the solvent, or ifthe components are employed neat, constitute the source of reflux, butin either case it is preferred at least to effectuate the reactionthrough intermediate stages with appropriate reaction times, to returnvolatiles to the reaction zone. Thus, butanol is generated when thetitanium component is titanium tetra n-butoxide forming a azeotrope withthe hydrocarbon solvent. Selection of solvent and/or alkoxide relativeto possible suppression of reaction temperature is accordingly aconsideration, as is known to one skilled in the art.

Reaction temperature will to some extent be a matter of choice within abroad range, depending upon the speed of reaction conveniently to beconducted. It has been found that the reaction system (constituted bythe liquid transition metal component, alkyl phosphates, reducing metalparticles and solvent, where desired) evidences visible gas generationat about 50°-70° C. suggesting an initiation temperature or activationenergy level at about 50° C. which therefore constitutes the minimumnecessary temperature for reaction of the polymeric oxide alkoxide withthe reducing metal. As the alkanol generated is largely consumed in thecourse of the continuing reaction (as an independent species), theactual system temperature will change, and completion of the reaction isevidenced by consumption of visible metal and evolution of gas within aperiod of as little as 10-15 minutes to 4 hours or more. Suchtemperatures may reach 140°-190° C. and of course higher temperaturesmight be imposed but without apparent benefit. It is most convenient tooperate within the range of 50°-190° C., preferably 70°-140° C. In theabsence of solvent, the upper limit will simply be established by thereflux temperature for the alkanol generated in the course of thereaction.

Reaction of the components is most clearly apparent from the markedcolor change, with exotherm, that accompanies commencement of gasevolution. Where lack of opacity or turbidity of the solution admitsobservation, evolution of gas ranging from bubbling to vigorouseffervescence is most evident at the surface of the magnesium metal, andthe generally light colored solutions immediately turn greyish, thenrapidly darker to blue, sometimes violet, usually blue black, sometimeswith a greenish tint. Analysis of the gas evidences no HCl; and isessentially H₂. Following the rapid color change some deepening of coloroccurs during a gradual increase of temperature, with continuing gasevolution.

The reaction product is hydrocarbon soluble at least in part, and ismaintained in slurry form for convenience in further use. The viscous tosemi-solid product, when isolated, evidences on X-ray diffractionanalysis, an essentially amorphous character. The color change andconsumption of reducing metal is believed to evidence at least partialreduction of the transition metal, hence reference to reduced polymerictransition metal oxide alkoxides. While reference herein is madeprincipally to the reducing potential of the metal, e.g., magnesiumreactant, it is believed that the metal values themselves which areretained in the catalyst precursor contribute structurally andfunctionally to the catalyst characteristics. Thus, it is believed thatthe magnesium metal in its oxidized state forms a part of the oxidealkoxide structure, as aforesaid, for example, linking through oxygen totransition metal, viz., forming --TiOMg-- linkages in the polymericstructure or, more generally, --TrOMr-- wherein Tr represents transitionmetal and Mr is reducing metal.

Molar ratios of the components may vary within certain ranges withoutsignificantly affecting the performance of the catalyst precursor inultimate use. Thus, to avoid competing reactions rendering the reactionproduct inconveniently gelatinous or intractable, the transition metalcomponent is ordinarily supplied in at least molar proportion relativeto the reducing metal, but the transition metal reducing metal ratio mayrange from about 0.5 to 1.0 to 3.0 to 1.0 or more, preferably 1/0.1-1/1.An insufficient level of reducing metal will result in suppression ofthe reaction temperature such that the reflux temperature of the puresolvent remains unattained; whereas an excess of reducing metal will beimmediately apparent from the unconsumed portion thereof, hence thedesired amount of this component is readily ascertained by one skilledin the art.

Within these ranges, a varying proportion of the reaction product mayconstitute a hydrocarbon insoluble component which, however, may be andcommonly is slurried with the soluble component for use, e.g., furtherreaction with a halide activator to form an olefin polymerizationcatalyst. The amount of such insoluble component may be controlled inpart by the use of a solvent with an appropriate partition coefficientbut where use of a common hydrocarbon solvent such as octane ispreferred for practical reasons, equimolar ratios of, e.g., Ti/Mg/alkylphosphates have been found most adapted to the formation of ahomogeneous reaction product.

The alkyl phosphates are also preferably supplied in molar ratio to thetransition metal component, for similar reasons of homogeneity and easeof reaction. The molar equivalence of the alkyl phosphate is calculatedon the basis of whether the phosphate is monoprotic or diprotic, for theformer, equimolar, and the latter, 0.5 molar equivalence. When mixturesof mono- and diprotic alkyl phosphates are used, the molar equivalenceis calculated on the basis of the percent of each species present in themixture. More generally, the alkyl phosphates may range from about 0.66to 3 moles per mole of transition metal. The full molar proportion ofalkyl phosphates may be supplied at the commencement of the reaction orthe compound may be added portionwise. The measured amount of alkylphosphates is essentially in molar balance or molar excess relative tothe reducing metal component and appears to be related to itsconsumption in the reaction, as a molar insufficiency will invariablyresult in excess reducing metal remaining. In general, a modest excessof alkyl phosphate of 10-40% is suitable to ensure complete reaction.Higher proportions are suitable without limitation but should be kept inrelative stoichiometric balance to the transition metal component.

A metal salt is also present in the reaction mixture and may serve todope the precursor with selected cations or act as a scavenger orexchange site for alkoxides. The preferred salts are those in which thecation is the same as the reducing metal, e.g., magnesium salts whenmagnesium is the reducing metal. Exemplary salts include magnesiumchloride, magnesium acetate, magnesium sulfate, magnesium siliconfluoride, sodium acetate, aluminum chloride, magnesium acetylacetonate,calcium chloride, nickel chloride, and ferric chloride.

In a preferred aspect of the invention the reaction product (catalystprecursor) is further interreacted with a halide activator.

By `halide activator` it is intended to denote a class of materialstypified by the presence of halogen understood to be abstractable orexchangeable in interreaction with transition metal catalyst precursors(although the presence of transition metal-halogen bonding cannot beconfirmed) and commonly employed in the Ziegler catalyst art, such asthe alkyl aluminum halides, silicon halides, alkyl silicon halides,titanium halides, boron halides and alkyl boron halides. These compoundsmay or may not have reducing potential as, in accordance with thepresent invention, they are normally reacted with the polymerictransition metal oxide alkoxides in the reduced state, i.e., wherein thetransition metal exists at least in significant part in a state belowits maximum oxidation potential. In the latter case, the polymerictransition metal oxide alkoxide is reacted with the reducing metal priorto interreaction thereof with the halide activator, i.e., the reactionsare carried out sequentially. The use of the reduced polymerictransition metal oxide alkoxides thus permits the utilization of suchnon-reducing halide activators as the silicon or boron halides,affording flexibility of operation and advantages such as reducedextractables in olefin resins produced therewith, e.g., isopentaneextractables of less than 6 wt. %, preferably less than 3 wt. % foras-produced polyethylene. It has been found that the catalyst precursormay be activated readily, by merely combining the product with thehalide activator. The reaction is vigorously exothermic, hence thehalide activator is typically added gradually to the reaction system,which may be maintained with cooling, e.g., to 10°-13° C. for ease ofhandling.

The halide activator is commonly supplied for interreaction at a molarratio of 3:1 to 6:1 (aluminum, silicon or boron, relative to thetransition metal) although ratios of 2:1 or more have been usedsuccessfully. Normally, upon completion of addition, the reaction isalso complete and may be terminated. The solid reaction product, orslurry may then be used immediately, or stored for future use. Usuallyfor best control over molecular weight characteristics, and particularlyfor production of low density resin, only the hydrocarbon washed solidreaction product is employed as the catalyst, although the supernatantis also catalytically active. In such case, the halogenated precursorslurry is settled and decanted a number of times with relatively largevolumes of hydrocarbon solvent. While any such solvent may be used, toavoid complexities in recovery or recycle the solvent for catalystpreparation, preferably n-octane is employed in the washing operation,in amounts of about 25:1 (wgt/wgt) of solvent to catalyst as transitionmetal.

The catalyst wash necessarily leads to some loss of transition metalvalues but reduces resin Cl⁻ levels, minimizes reactor fouling andprovides improved polymer morphology. Elemental analysis (wgt % ofisolated solids) shows Ti 6.3%, Mg 11.4%, Si 5.1%, and Cl 46.8% for a1/0.75/0.128 catalyst precursor formed from TBT/Mg°/MgCl₂.6H₂ O,activated with 3/1 SiCl₄.

The resultant catalyst product may be used directly in thepolymerization reaction although it is typically diluted, extended orreduced as required to provide in a convenient feed an amount ofcatalyst equivalent to 80-100 mg/transition metal based upon a nominalproductivity of greater than 200,000 gm polymer/gm transition metal incontinuous polymerizations which the present catalyst typically exceeds(e.g., 250,000 to 1,000,000 g/g). Adjustments are made by the artisan toreflect reactivity and efficiency, ordinarily by mere dilution, andcontrol of feed rates.

The transition metal containing catalyst is suitably combined for use inolefin polymerization with an organometallic cocatalyst such as triethylaluminum or triisobutyl aluminum or a non-metallic compound such astriethylborane. A typical polymerizer feed thus comprises 42 parts ofisobutane solvent, 25 parts of ethylene, 0.0002 parts of catalyst(calculated as Ti), and 0.009 parts co-catalyst (TEA, Calculated as Al),provided to a reactor maintained at 650 psig. and 160° F. In general,the amount of co-catalyst, where employed is calculated to range frombetween about 30 to 50 ppm calculated as Al or B, based upon isobutane.In general, the activity of the catalyst is responsive to the molarratio of the co-catalysts, i.e., high ratios of, e.g., Al/Ti into therange of 24/1 to 48/1 or more, correlate with higher activity levels.

Examples of metallic co-catalysts include trialkyl aluminums, such astriethyl aluminum, triisobutyl aluminum, and tri-n-octyl aluminum, alkylaluminum halides, alkyl aluminum alkoxides, dialkyl zinc, dialkylmagnesium, and metal borohydrides including those of the alkali metals,especially sodium, lithium and potassium, and of magnesium, berylliumand aluminum. The non-metal co-catalysts include boron alkyls such astriethyl borane, triisobutyl borane and trimethyl borane and hydrides ofboron such as diborane, pentaborane, hexaborane and decaborane.

The polymerization reactor is preferably a loop reactor adapted forslurry operation, thus employing a solvent such as isobutane from whichthe polymer separates as a granular solid. The polymerization reactionis conducted at low pressure, e.g., 200 to 1000 psi and a temperature inthe range of 100° to 200° F. with applied hydrogen as desired to controlmolecular weight distribution. The polymerization may nevertheless beconducted at higher pressures, e.g., 20,000 to 40,000 psi, in autoclaveand tubular reactors, where desired.

Other n-alkenes may be fed to the reactor in minor proportion toethylene, for copolymerization therewith. Typically, butene-1 or amixture thereof with hexene-1 or octene-1 is employed, in an amount of 3to 10 mol%, although other alpha olefin comonomers/proportions may bereadily used. In utilizing such n-alkene comonomers, one may secureresin densities over the range from 0.91 to 0.96. Still other alphaolefin comonomers, such as 4-methyl-pentene-1, 3-methyl-butene-1,isobutylene, 1-heptene, 1-decene, or 1-dodecene may be used, from aslittle as 0.2% by weight, especially where monomer admixtures areemployed.

In referring herein to an intermetallic "compound" or "complex" it isintended to denote any product of reaction, whether by coordination orassociation, or in the form of one or more inclusion or occlusioncompounds, clusters, or other interengagement under the applicableconditions, the integrated reaction in general being evidenced by colorchange and gas evolution, probably reflective of reduction-oxidation,rearrangement and association among the unconsumed elements of thereaction system.

The following example further illustrates the invention.

EXAMPLE I

Technical grade dibutyl phosphate (DBP) is in a mixture of 55% (BuO)₂P(O)(OH) and 45% BuOP(O)(OH)₂ with a weighted molecular weight of 184.96and 1.45 moles of (OH) per mole of phosphorus.

A mixture of 85.1 g (0.25 m) titanium tetrabutoxide 85.1 g octane, 4.56g (0.1875 m) Mg turnings, 4.57 g (0.048 m) MgCl₂ and 24.51 (0.132 m) DBPwas stirred in a reaction flask. On mixing, the temperature increasedfrom 24° to 43° C. On heating to 48° C., the mixture changed to lightpurple color and gas evolution commenced. As the temperature wasincreased, the color darkened and gas evolution became more rapid toeffervescence at 110° C. The color of the mixture was yellow brown atthis point. Finally, at 127° C. a pea green liquid resulted and nofurther evolution of gas was noticed.

The reaction mixture was centrifuged to obtain a blue liquid and peagreen precipitate. All of the magnesium had reacted as evidenced by theabsence of magnesium turnings in the reaction vessel.

The reaction product may be activated in known manner with, e.g., analkyl aluminum halide, a boron halide or a silicon halide by reactiontherewith, conveniently at a molar ratio of about 3:1 to 6:1 (Al orSi/Ti) to provide, in combination with an organic or organometallicreducing agent, an olefin polymerization catalyst adapted to theformation of polyethylene resin.

Thus, the titanium-containing reaction product is combined with silicontetrachloride at a molar ratio of 3:1 with cooling to 10°-13° C. Uponcompletion of the exothermic reaction, the solid reaction product may behydrocarbon washed and stored or combined for use in olefinpolymerization with, for example, triethyl aluminum or triisobutylaluminum.

What is claimed:
 1. An intermetallic compound comprising the reactionproduct of a transition metal and a reducing metal of a higher oxidationpotential than the transition metal obtained by the reaction at elevatedtemperature of a polymeric transition metal oxide alkoxide and thereducing metal in the presence of a mono- or dialkyl phosphate ormixtures thereof in which each alkyl contains up to 10 carbon atoms. 2.The intermetallic compound of claim 1 wherein the transition metal istitanium or zirconium.
 3. The intermetallic compound of claim 2 whereinthe reducing metal is magnesium.
 4. The intermetallic compound of claim1 wherein the transition metal is titanium and the reducing metal ismagnesium.
 5. The intermetallic compound of claim 4 wherein saidtitanium and said magnesium are present in a molar ratio of from about0.5:1 to about 3:1.
 6. An intermetallic compound comprising metal valuescomposed predominantly of titanium and magnesium values obtained byreaction at elevated temperature of a titanium alkoxide and magnesiummetal in the presence of a mono- or dialkyl phosphate or mixturesthereof in which each alkyl group contains up to 10 carbon atoms for aperiod of time sufficient to consume the magnesium metal.
 7. Theintermetallic compound of claim 6 which is hydrocarbon soluble.
 8. Theintermetallic compound of claim 6 wherein said titanium alkoxide istitanium tetra n-butoxide.
 9. The intermediate compound of claim 6wherein each alkyl group contains up to 5 carbon atoms.
 10. Theintermediate compound of claim 6 wherein said phosphate is a mixture ofmono- and dibutyl phosphate.
 11. A catalyst component for polymerizationof alpha olefins comprising the intermetallic compound of any of claims1-6 further reacted with a halide activator selected from the groupconsisting of alkyl aluminum halides, silicon halides, alkyl siliconhalides titanium halides, boron halides and alkyl boron halides.
 12. Thecatalyst component of claim 11 wherein the molar ratio of said halideactivator to said intermetallic compound is between about 2.5/1 to about6/1 as Al/Ti, Si/Ti, Ti/Ti, or B/Ti.
 13. A catalyst system for thepolymerization of alpha olefins comprising the catalyst component ofclaim 11 and an organo aluminum compound.
 14. The catalyst system ofclaim 13 wherein said organo aluminum compound is triethyl aluminum. 15.A catalyst system for the polymerization of alpha olefins comprising thecatalyst component of claim 11 and an organo boron compound.
 16. Thecatalyst system of claim 12 wherein said organo borane compound istriethyl borane.
 17. A process for the preparation of an intermetalliccompound which comprises reacting at elevated temperature a polymerictransition metal oxide alkoxide with a reducing metal of higheroxidation potential than the transition metal in the presence of a monoor dialkyl phosphate, or a mixture thereof, in which each alkyl groupcontains up to 10 carbon atoms for a period of time sufficient toconsume the magnesium metal.
 18. A process according to claim 17 whereinsaid transition metal is titanium or zirconium.
 19. A process accordingto claim 18 wherein the reducing metal is magnesium.
 20. A processaccording to claim 17 wherein the transition metal is titanium and thereducing metal is magnesium.
 21. A process according to claim 17 whereinthe product is further reacted with a halide activator.